1 files changed, 38 insertions, 0 deletions
diff --git a/src/test/scala/firrtlTests/graph/DiGraphTests.scala b/src/test/scala/firrtlTests/graph/DiGraphTests.scala
new file mode 100644
index 00000000..6546e147
--- /dev/null
+++ b/src/test/scala/firrtlTests/graph/DiGraphTests.scala
@@ -0,0 +1,38 @@
+package firrtlTests.graph
+
+import java.io._
+import org.scalatest._
+import org.scalatest.prop._
+import org.scalatest.Matchers._
+import firrtl.graph._
+import firrtlTests._
+
+class DiGraphTests extends FirrtlFlatSpec {
+
+  val acyclicGraph = DiGraph(Map(
+    "a" -> Set("b","c"),
+    "b" -> Set("d"),
+    "c" -> Set("d"),
+    "d" -> Set("e"),
+    "e" -> Set.empty[String]))
+
+  val cyclicGraph = DiGraph(Map(
+    "a" -> Set("b","c"),
+    "b" -> Set("d"),
+    "c" -> Set("d"),
+    "d" -> Set("a")))
+
+
+  acyclicGraph.findSCCs.filter(_.length > 1) shouldBe empty
+
+  cyclicGraph.findSCCs.filter(_.length > 1) should not be empty
+
+  acyclicGraph.path("a","e") should not be empty
+
+  an [acyclicGraph.PathNotFoundException] should be thrownBy acyclicGraph.path("e","a")
+
+  acyclicGraph.linearize.head should equal ("a")
+
+  a [cyclicGraph.CyclicException] should be thrownBy cyclicGraph.linearize
+
+}